The invention relates a protective hood for grinding machines, particularly for angle grinders, and a suitable fastening receptacle for the latter. In grinding machines, an allowable circumferential speed of the clamped-in grinding disk should not be exceeded. The maximum allowable grinding disk diameter is dependent on the normal speed of the machine. Thus, taking this into account, only grinding disks up to a maximum allowable diameter may be clamped in. In order to be able to exert influence over this, it is known that grinding machines which are smaller with respect to their output are dimensioned so as to be smaller, with respect to a cylindrical fastening shoulder, than machines having a higher output. Accordingly, only protective hoods whose securing part is likewise dimensioned so as to be correspondingly small fit on the smaller fastening shoulder. Such small protective hoods then only allow grinding disks to be clamped on which are, at most, the same size as, but not larger than, the protective hood. It is known, according to this principle, to effect rough gradations with two different diameters of the fastening shoulder. Aside from the fact that such a rough gradation is insufficient, variously dimensioned cast parts, different machine adjustments while utilizing the machine, and also different suitably fitting accessories are necessary. This is costly and cumbersome. Because of the need for different machine adjustments during the machining, handling becomes impractical.